Clinical and microbiological evaluation of temocillin for bloodstream infections with Enterobacterales: a Belgian single-centre retrospective study.

Background: Expanding the use of temocillin could be an important weapon in the fight against antimicrobial resistance. However, EUCAST defined clinical breakpoints for a limited number of species and only for urinary tract infections (UTI), including urosepsis but excluding severe sepsis and septic shock. Moreover, a dosage of 2 g q8h is advised in most cases. Objectives: Evaluation of temocillin use for the treatment of bacteraemia, correlating clinical and microbiological outcomes with infection site, infection severity, temocillin dosage, Enterobacterales species and MIC. Patients and methods: All adult patients with blood cultures positive for temocillin-susceptible Enterobacterales and treated with temocillin for ≥72 h from June 2018 until June 2021 were considered for inclusion. The primary outcome was clinical success, defined as resolution of infection signs, no relapse of the same infection and no antibiotic switch due to insufficient clinical improvement. The secondary outcome was microbiological success. Results: In total, 182 episodes were included [140 UTI versus 42 non-UTI, 171 Escherichia coli, Klebsiella species (except Klebsiella aerogenes) and Proteus mirabilis (EKPs) versus 11 non-EKPs]. Clinical and microbiological failure were low (8% and 3%, respectively). No difference in outcome was observed for dosages of 2 g q12h versus 2 g q8h, either for EKP versus non-EKP isolates or MIC values ≤8 versus 16 mg/L. Considering only bacteraemia episodes of UTI origin, using the 16 mg/L breakpoint, there was no difference in success rate between regimens of 2 g q12h and 2 g q8h. Conclusions: Temocillin 2 g q12h can be successfully used for the treatment of systemic UTI. Prospective studies are needed to assess outcomes and evaluate non-inferiority compared with other broad-spectrum antibiotics in non-UTI infections, including bacteraemia.

Multicenter evaluation of the revised RIDA® QUICK test (N1402) for rapid detection of norovirus in a diagnostic laboratory setting.

The updated RIDA® QUICK (N1402) immunochromatographic assay (R-Biopharm) for detection of norovirus was evaluated during a prospective, multicenter study using 771 stool samples from patients with gastroenteritis. Compared to real-time reverse transcriptase polymerase chain reaction (RT-rtPCR) as gold standard, the RIDA® QUICK had an overall sensitivity of 72.8% (91/125) and a specificity of 99.5% (640/643). Genotype analysis of the polymerase (ORF1) and capsid (ORF2) region of the genome indicated that the RIDA® QUICK assay could detect a broad range of genotypes including new variants (15 of 125 positive samples) which were detected by an in-house SYBR®Green RT-rtPCR, but not by the RIDA® GENE PCR PG1415 (R-Biopharm) and mostly not by the RIDA® GENE PCR PG1405 and the Xpert® Norovirus assay (Cepheid). The RIDA® QUICK can be used to reliably confirm norovirus in stool samples, but a negative result does not definitively exclude the presence of norovirus.

The preanalytical optimization of blood cultures: a review and the clinical importance of benchmarking in 5 Belgian hospitals.

Bloodstream infections remain a major challenge in medicine. Optimal detection of pathogens is only possible if the quality of preanalytical factors is thoroughly controlled. Since the laboratory is responsible for this preanalytical phase, the quality control of critical factors should be integrated in its quality control program. The numerous recommendations regarding blood culture collection contain controversies. Only an unambiguous guideline permits standardization and interlaboratory quality control. We present an evidence-based concise guideline of critical preanalytical determinants for blood culture collection and summarize key performance indicators with their concomitant target values. In an attempt to benchmark, we compared the true-positive rate, contamination rate, and collected blood volume of blood culture bottles in 5 Belgian hospital laboratories. The true-positive blood culture rate fell within previously defined acceptation criteria by Baron et al. (2005) in all 5 hospitals, whereas the contamination rate exceeded the target value in 4 locations. Most unexpected, in each of the 5 laboratories, more than one third of the blood culture bottles were incorrectly filled, irrespective of the manufacturer of the blood culture vials. As a consequence of this shortcoming, one manufacturer recently developed an automatic blood volume monitoring system. In conclusion, clear recommendations for standardized blood culture collection combined with quality control of critical factors of the preanalytical phase are essential for diagnostic blood culture improvement.

Performance of a new chromogenic medium, BBL CHROMagar MRSA II (BD), for detection of methicillin-resistant Staphylococcus aureus in screening samples.

Two chromogenic media for the detection of MRSA were compared: BBL CHROMagar MRSA II (BD) and MRSA ID agar (bioMérieux). Following overnight nonselective enrichment, 1,919 screening samples were inoculated on both chromogenic agars. After 24 h, the sensitivities of both media were high and comparable. Both media showed an important decrease in specificity after 48 h of incubation (decreases of 8% for MRSA II and 10% for MRSA ID), but MRSA II was significantly more specific at both time points.

Different clonal complexes of methicillin-resistant Staphylococcus aureus are disseminated in the Euregio Meuse-Rhine region.

The Euregio Meuse-Rhine (EMR) is formed by the border regions of Belgium, Germany, and The Netherlands. Cross-border health care requires infection control measures, in particular since the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) differs among the three countries. To investigate the dissemination of MRSA in the EMR, 152 MRSA isolates were characterized by pulsed-field gel electrophoresis (PFGE), SCCmec typing, and multilocus sequence typing. PFGE revealed major clonal groups A, G, L, and Q, suggesting dissemination of MRSA in the EMR. Group A harbored mainly SCCmec type III and sequence types (STs) 239 and 241. The majority of the strains from group G harbored SCCmec type I and ST8 and ST247, whereas most strains from group L carried either SCCmec type IV or type I. Within group L, ST8 and ST228 were found, belonging to clonal complexes 8 and 5, respectively. Most strains from group Q included SCCmec type II and were sequence typed as ST225. Both ST225-MRSA-II and ST241-MRSA-III were novel findings in Germany. In addition, the SCCmec type of two isolates has not been described previously. One strain was classified as SCCmec type III but harbored the pls gene and the dcs region. Another strain was characterized as SCCmec type IV but lacked the dcs region. In addition, one isolate harbored both SCCmec type V and Panton-Valentine leukocidin. Finally, the SCCmec type of the strains was found to be correlated with the antibiotic susceptibility pattern.